Vacuum abatement systems, which prevent contaminants from reaching critical printer components, typically consist of a manifold or nozzle, a vacuum source (e.g. blower or fan) and ducting to connect the vacuum source and the manifold. Physically separating the manifold and blower allows the manifold to be embedded in the architecture, closely spaced from the surfaces or elements being cleaned, with the blower located in some less space-restricted area. The drawback is the creation of additional resistance to abatement airflow by the connecting duct, which is often long and can have many bends. In addition to degrading the airflow in the abatement system, the ducting adds complexity and cost. The ducting itself may consist of several components, and connections and seals are needed on both the blower and manifold ends of the duct.
As also discussed in U.S. Patent Publication 2003/0170043 (incorporated herein by reference) dust, debris, and toner may adversely affect the development operation in image-forming machines. Dust from each development station may adversely affect the development process in the other development stations. If similarly charged, the airborne toner from one development station may adhere to the photoconductor in place of the toner from another development station. The blending of toner from different development stations also adversely affects the toner properties and subsequently the image quality. If oppositely charged, the airborne toner may blend with the toner from the other development station and may then be attracted to the non-image areas producing a background or fog in the image.
Some image-forming machines implement one or more approaches to remove or otherwise control the airborne toner and carrier. See, for example, U.S. Patent Publication 2003/0052545, and U.S. Pat. Nos. 5,081,496, and 5,066,983 (all incorporated herein by reference) which utilize an external fan connected to a tube to create a vacuum near the cartridge or drum. A vacuum pump, fan, or other air movement device may be used to remove and filter the airborne toner from the air within the image-forming machine. Smaller vacuum pumps may be used to remove toner stacks or other build-up of toner in the image-forming machine. Some image-forming machines have a vacuum or electrostatic tube with several openings for applying a vacuum or an electrostatic charge along the trailing edge of the development station. These trailing edge openings collect airborne toner and carrier exiting along the trailing edge.